Add data components 151-175; clear MyGo row highlights

Lists, tables, trees, grids, inventories and records in data/.
Outline and GridView build on ui.List: ui.Outline strokes its arrows
and ui.GridView spaces and tints items. The pixel theme keeps MyGo's
row highlights clear so scrolled rows stay on whole dots; off lists
take a veil against the wheel. Adds Canvas.Silhouette, SwitchOptions
Label and exports Rarity.Slot.

data/leaderboard.go

@@ -0,0 +1,59 @@
+package data
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/egoist/mygo/ui"
+
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/display"
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/text"
+)
+
+// Score is a leaderboard entry.
+type Score struct {
+	Name  string
+	Score int
+}
+
+type LeaderboardOptions struct {
+	// Player is your row, marked; -1 marks none.
+	Player int
+}
+
+// Leaderboard ranks scores; the top three wear medals.
+func Leaderboard(c *ui.Context, scores []Score, o LeaderboardOptions) *ui.Element {
+	k := pixel.K(c)
+	if o.Player < -1 || o.Player >= len(scores) {
+		panic(fmt.Sprintf("data: Leaderboard Player %d of %d", o.Player, len(scores)))
+	}
+	return ui.Column(c).AlignItems(ui.Stretch).Role(ui.RoleTable).Children(func() {
+		for i, s := range scores {
+			you, ink := i == o.Player, pixel.Ink
+			if you {
+				ink = pixel.AccentInk
+			}
+			ui.Row(c).Height(k.D(pixel.LineHeight+4)).Gap(k.D(6)).Padding(0, k.D(4)).AlignItems(ui.Center).Role(ui.RoleRow).
+				Label(fmt.Sprintf("%d %s %d", i+1, s.Name, s.Score)).Draw(func(p *ui.Painter, r ui.Rect) {
+				g := k.Canvas(p, r)
+				if you {
+					g.Rect(0, 0, g.W, g.H, pixel.Accent)
+				} else if i%2 == 1 {
+					g.Veil(0, 0, g.W, g.H, pixel.Shade, 4)
+				}
+			}).Children(func() {
+				ui.Box(c).Width(k.D(14)).Shrink(0).AlignItems(ui.Center).Children(func() {
+					if i < 3 {
+						display.Medal(c, display.Rank(i), display.MedalOptions{})
+					} else {
+						text.MicroText(c, strconv.Itoa(i+1), text.MicroTextOptions{Slot: ink})
+					}
+				})
+				pixel.Text(c, s.Name, pixel.TextOptions{Slot: ink})
+				ui.Box(c).Grow(1)
+				text.MicroText(c, fmt.Sprintf("%07d", s.Score), text.MicroTextOptions{Slot: ink})
+			})
+		}
+	})
+}